The present invention relates to a production system using a plurality of different combination jigs and a jig replacement method and a jig replacement apparatus therefore. More specifically, the invention relates to a production system equipped with a production line, preferably a laser welding line, including a line section using a combination jig and having a gateway extending therealong, and to a jig replacement method and a jig replacement apparatus therefore.
A laser welding line for production of an automobile body includes a number of line sections each dedicated for butt welding pieces of a work along a particular weld line, such as between sheet pieces of a door outer panel different of antecedent process or treatment or in configuration or thickness, as necessary for cost-effective production of a weight-reduced product, and a respective line section employs a dedicated one of different combination jigs for work pieces to be thereby held so as to abut on each other to be butt welded along a corresponding weld line.
Such a combination jig may preferably be selected for and replaced from time to time at a common line section for butt welding.
In this respect, a respective combination jig comprises a pair of upper and lower jigs. The lower jig is installed on a base. The upper jig is adapted for handling work pieces to be loaded on the lower jig, and cooperates with the lower jig to pinch the work pieces therebetween, under assistance of a gateway that extends along the line section and supports and longitudinally carries the upper jig.
The upper and lower jigs are both great and heavy, e.g. several tons of weight, and need a mechanical transfer to and from the line section which has a two-dimensional density of auxiliary equipment installed therearound, such as a laser head handling framework standing astride the gateway.
The gateway may preferably serve for carrying both upper and lower jigs to longitudinally load them in a work region.
However, such a gateway has cross members with suspended appliances, such as utility lines and a work unloader, which may impede a longitudinal transfer of the jigs, constituting an obstacle to efficient production.
The present invention has been achieved with such points in view.
It therefore is an object of the invention to provide a production system using a plurality of different combination jigs, as well as a jig replacement method and a jig replacement apparatus therefore, permitting smooth jig replacement, allowing efficient production.
To achieve the object described, an aspect of the invention provides a production system comprising an elongate work region for an arbitrary one of different combination jigs to be handled therein to thereby hold a work to be processed, preferably for a laser processing (in particular for a butt welding), a gateway extending astride the work region and adapted to longitudinally carry an upper jig portion of the arbitrary combination jig, and a rail line to guide the arbitrary combination jig into and out of the work region transversely of the gateway.
Further, to achieve the object, another aspect of the invention provides a jig replacement method for a production system including an elongate work region for an arbitrary one of different combination jigs to be handled therein to thereby hold a work to be processed, preferably for a laser processing (in particular for a butt welding), and a gateway extending astride the work region and adapted to longitudinally carry an upper jig portion of the arbitrary combination jig, the jig replacement method comprising guiding the arbitrary combination jig into the work region transversely of the gateway, and guiding the arbitrary combination jig out of the work region transversely of the gateway.
Another aspect of the invention provides a jig replacement method for replacing a lower jig set on a base, and an upper jig adapted to cooperate with the lower jig for pinching to secure therebetween a work to be subjected to a processing, hold the work and move along a guide rail between from a work loading position, where the work is carried in from outside, to a work position for the processing, the jig replacement method comprising the steps of upwardly moving the upper jig to be free from an upper jig clamp, as the upper jig is released from the clamp at a side edge thereof, moving the upper jig clamp to the work loading position, downwardly moving the upper jig to be placed on the lower jig, upwardly moving a jig transfer guide rail extending in a perpendicular direction to the guide rail, supporting the lower jig by the jig transfer guide rail together with the upper jig, moving the guide rail to a position out of a movement range for the jigs to be carried along the jig transfer guide rail, and carrying the jigs outside along the jig transfer guide rail.
Further, to achieve the object, another aspect of the invention provides a jig replacement apparatus for replacing a lower jig set on a base, and an upper jig adapted to cooperate with the lower jig for pinching to secure therebetween a work to be subjected to a processing, hold the work and move along a guide rail between from a work loading position, where the work is carried in from outside, to a work position for the processing, the jig replacement apparatus comprising a loader movable on the guide rail, an upper jig clamp provided on the loader and having a jig receiver for a side edge of the upper jig to be placed thereon and a vertically movable member to be moved downward from above the jig receiver to clamp therebetween the side edge of the upper jig, an upper jig lift adapted, when the upper jig is released from the upper jig clamp as the vertically movable member is moved upward, to lift the upper jig to render the loader movable together with the upper jig clamp to the work loading position, a jig transfer guide rail normally downwardly spaced from the lower jig and adapted, when the loader is moved together with the upper jig clamp to the work loading position and the upper jig is placed on the lower jig as the upper jig is downwardly moved by the upper jig lift, to guide the upper and lower jigs to be moved in a perpendicular direction to the guide rail, a rail lift adapted to lift the jig transfer guide rail to support the lower jig, as the upper jig is placed thereon, and a guide rail lift adapted to move the guide rail to have a movement range secured for the lower jig to be moved together with the upper jig along the jig transfer guide rail, as the jig transfer guide rail is lifted by the rail lift, for one of loading and unloading of the upper and lower jigs relative to outside.